Despite presiding over, and indeed fostering, a booming economy and relative stability in international affairs, Trump’s job approval never rose above 50% in the RealClearPolitics polling average. Obviously, some voters loved him. But he was not widely liked. If he ran again, his penchant for catering mostly to voters in his base rather than winning independents and his insatiable demand for political loyalty would dangerously split the Republican presidential primary, for he would force opponents to separate themselves from him. This would create two problems. First, Trump’s unmatched and apparently unquenchable sense of grievance would roar back to the top of national attention. In recent months, Trump has trained his fire on Republicans and conservatives he thinks wronged him, including Senate Minority Leader Mitch McConnell, former Attorney General Bill Barr, and even Supreme Court Justice Brett Kavanaugh. Second, Trump regards any challenge or lack of willingness to defend him at any cost as unforgivable. In the GOP presidential primary, Trump wouldn’t think twice about attacking the strong records of other attractive candidates such as Florida Gov. Ron DeSantis, South Dakota Gov. Kristi Noem, or Texas Gov. Greg Abbott. This would force them to distinguish themselves from Trump, which would alienate them from his voters, whom the party has worked to retain and attract since 2016. As the GOP’s most recent president, Trump would be in the strongest position in the primary to define the party and demand conformity. Challengers are at a big disadvantage. Trump’s fundraising capabilities and his grip on state Republicans give him a significant edge before a single vote is cast.